Appending mixed types to strings seems a bit tricky. Is this the intended behaviour?

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I understand why I get different results, but is seems wrong. Is this intended?
'1' + "1" + 1
ans = "111"
'1' + 1 + "1"
ans = "501"

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Rik
Rik il 27 Set 2022
Modificato: Rik il 27 Set 2022
It helps to do this step by step, which show that (while unintuitive), this is intended behavior.
Matlab evaluates code from left to right:
'1' + "1"
ans = "11"
ans + 1
ans = "111"
And your second example:
'1' + 1
ans = 50
ans + "1"
ans = "501"
Because the first call to plus doesn't know you want to use a string as an operand later, this results in a conversion to double, and since the UTF-16 encoding of '1' is uint16(49), this results in double(50).
You can avoid this by putting in some parentheses:
'1' + ( 1 + "1" )
ans = "111"
  6 Commenti
Stephen23
Stephen23 il 27 Set 2022
"I never considered that code is strictly evaluated left to right."
This is explained in the MATLAB documentation: "Within each precedence level, operators have equal precedence and are evaluated from left to right". Plusses all have the same precedence.
Tomazz
Tomazz il 27 Set 2022
Sure, it makes sense.
Still, I was a bit surprised that (S1+S2)+S3 is not equal to S1+(S2+S3) in this case.

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